Chapter 13: Toxicology and Anticancer Activity of Synthetic Organoselenium Compounds

This chapter describes briefly the toxicity of selenium compounds with a special emphasis on synthetic organoselenium compounds. Since the discovery of selenium in the 19th century, several studies have been published about the paradoxical health and toxic effects of selenium. The essentiality of selenium to life is directly related to its incorporation into a small number of proteins, selenoproteins, most of them with antioxidant activity. Conversely, the toxicity of selenium is related to the pro-oxidant activity of selenium metabolites and the consequent generation of reactive species. Selenium compounds, based on their anti- and pro-oxidant activity have been used as potential chemopreventive and chemotherapeutic agents. The use of selenium in cancer treatment is summarized. Futhermore, synthetic organoselenium compounds, for instance, ebselen, diselenides, selenocyanates and 3′-azido-3′-deoxythymidine (AZT) derivatives, are presented as potential anticancer agents. Finally, the main target molecules forcancer therapy related to the organoselenium compounds are presented, based in an in silico vision.